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    List of Articles علیرضا محمدیون


  • Article

    1 - شناسایی مودال ساختار ماشینهای دوار با استفاده از روش تخمین
    Journal of Mechanical Engineering and Vibration , Issue 2 , Year , Autumn 2018
    این مقاله به شناسایی مودال ساختار ماشینهای دوار با استفاده از روش تخمین طی دو آزمایش می‌پردازد. آزمایش1) شناسایی یک سیستم کامل بدون نیاز به اندازه گیری یک ردیف از ماتریس FRF درحالیکه یک ستون ماتریس مشخص باشد، با استفاده از یک مدل شبیه سازی روتور با چهار درجه آزادی. آزم More
    این مقاله به شناسایی مودال ساختار ماشینهای دوار با استفاده از روش تخمین طی دو آزمایش می‌پردازد. آزمایش1) شناسایی یک سیستم کامل بدون نیاز به اندازه گیری یک ردیف از ماتریس FRF درحالیکه یک ستون ماتریس مشخص باشد، با استفاده از یک مدل شبیه سازی روتور با چهار درجه آزادی. آزمایش2) شناسایی پارامترهای موجود در یک سیستم صنعتی که در آزمایش1 نمایان نشده است. سیستم آزمایشی یک سیستم ارتعاشی پیوسته بوده بنابراین شناسایی آن نیازمند استفاده از روشی است که آنرا به مانند یک سیستم گسسته توصیف کند و اغتشاش در اندازه گیریها نشان داده شده تا بتوان سیستم پیوسته را با یک مدل کوتاه در محدوده ی فرکانسی معین بیان کرد، آنگاه امکان تخمین پارامترهای مودال آن وجود دارد. همچنین نشان داده شد که دقتی که با آن بردارهای ویژه چپ تعیین می شوند می‌تواند تحت تاثیر دقتی باشد که با آن ثابت های مودال مربوط به همان مودها، از داده های اندازه گیری شده، تعیین می‌گردند. بنابراین می‌توان این نتیجه را گرفت که بردارهای ویژه چپ خود تحت تاثیر حضور اغتشاش موجود در اندازه گیری قرار خواهند گرفت. اثرات وجود اغتشاش برای درجات آزادی با دامنه های پاسخ کوچک برای نواحی فرکانسی در مجاورت مودهای نزدیک به هم، برجسته تر خواهد بود. همچنین علیرغم وجود ارتعاش، بردارهای ویژه چپ پیش بینی شده برای مشخص کردن یک ردیف از ماتریسFRF با استفاده از اندازه گیری یکی از ستون های آن مناسب است. Manuscript profile

  • Article

    2 - Optimizing AGV Colonie’s Efficiency by Fuzzy Simulation
    International Journal of Smart Electrical Engineering , Issue 2 , Year , Spring 2017
    This is an adoptive design of ant colony system and has been generalised to AGV transport system, predetermined targets replacement results has been evaluated simulating four AGV in Mat lab by Particle Algorithm and fuzzification and simulating the operative environment More
    This is an adoptive design of ant colony system and has been generalised to AGV transport system, predetermined targets replacement results has been evaluated simulating four AGV in Mat lab by Particle Algorithm and fuzzification and simulating the operative environment with regard to constant velocity and different results has been compared to each other by changing robots’ location and replacement of obstacles in the environment and using laser guidance system. Optimising considered sensor’s arrays led to more efficient and faster feedback. Regarding improvements mentioned, AGVs passing the obstacles with ease, choosing the shortest distance to the target and are flexible enough in case of one of the AGVs failure. 1- The AGV that has worked less than the others (from distance perspective), 2- the AGV which has been the closest to the failed AGV and 3- the AGV that has replaced fewer load. in fact, the system was able to operate more efficiently than when using an AGV. Manuscript profile

  • Article

    3 - Error Recovery by the Use of Sensory Feedback and Reference Measurements for Robotic Assembly
    International Journal of Smart Electrical Engineering , Issue 2 , Year , Spring 2017
    Industrial robots need instrument or parts transport to do which requires coordinate to show the robot’s instrument, parts and body. When investigating the robot location, we are usually interested in measuring its location relative to a reference coordinate syste More
    Industrial robots need instrument or parts transport to do which requires coordinate to show the robot’s instrument, parts and body. When investigating the robot location, we are usually interested in measuring its location relative to a reference coordinate system. In this system it is attempted to make the assemble direction smaller by designing the sensor board and making use of an instrument for self-adaptation of the gripper to the gripper working environment pallet. In addition, in order to eliminate the robot errors and parts transport system errors to the robot, there are different models employed using different sensors. In this research, the LASER sensors are used based on their applicability and cost. In present article, the V-REP software is used in order to simulate the mechanism. Considering the simulation results it can be stated that the RCC is an optimal model. Based on explained models in different sections of the article, this model can eliminate many of the errors in assemble by an optimal structure and reliable restriction and considering the geometrical uncertainty; for example, nail and hole, unreliability of friction coefficient etc. in addition, this model helps the fragile plastic parts assemble. Manuscript profile

  • Article

    4 - The Identification of the Modal Parameters of Orbital Machines using Dynamic Structural Approach
    International Journal of Smart Electrical Engineering , Issue 1 , Year , Winter 2018
    The researcher measured the least number of frequency response functions required for the identification of modal parameters, in order to simplify the identification of modal properties of such systems. In this work, the orbital machines are supposed to be a combination More
    The researcher measured the least number of frequency response functions required for the identification of modal parameters, in order to simplify the identification of modal properties of such systems. In this work, the orbital machines are supposed to be a combination of orbital and non-orbital components. Structural Approach specified the identification of dynamic properties only to those phrases that contain responses to a driving force. It has been revealed that the identification of dynamic properties distinguishes the orbital and non-orbital components of the structures and as a result, non-symmetric sections of the space coordinate matrixes become obvious. The application of the above approach was examined on two different structures. The first examination was on a computer-simulated rotor model with four degrees of freedom. In this case, the theoretical properties of this approach were evaluated, while the noise factor was disregarded. The second examination was done on a true machine, whereby the probable problems of the implementation of the suggested approach were clarified. The complete modal identification of an orbital system takes place without the need to measure a complete row of FRF matrixes. The number of the elements to be measured in an FRF matrix depends on the number of degrees of freedom of the system and on the non-symmetric sections of the stuffiness and damping matrixes. The number of elements of the left specific axis that should be measured directly from the evaluated data depends on the matrix sub-ranks, which is composed of non-symmetric sections of space-featured matrixes. Manuscript profile

  • Article

    5 - Performance Analysis of an Industrial Robot Under Uniform Temperature Change
    International Journal of Smart Electrical Engineering , Issue 1 , Year , Winter 2019
    The effect of temperature change on dynamic performances of an industrial robot with six axes of freedom is studied in this paper. In general, the strain and stress are produced not only by the external exciting force, but also by temperature change. The strain energy t More
    The effect of temperature change on dynamic performances of an industrial robot with six axes of freedom is studied in this paper. In general, the strain and stress are produced not only by the external exciting force, but also by temperature change. The strain energy that is caused by temperatureThis paper describes how the temperature variation effects the dynamic performance of an industrial robot with six axes of freedom. For the purposeedesign and construction of multi axes data acquisition and logging system, which could be used to collect a number of parameters from several sources by means of different types of transducers. The design of the system concentrated on the use of both inductive position and platinum film temperature sensors. The series of tests for investigating the robot performance regarding positioning repeatability and accuracy and their associated results did reveal that the multi axes data acquisition system operated satisfactorily.This work has also demonstrated that thermal expansion plays a significant role in variation of repeatability during warm-up period of the Rediffusion robot. Manuscript profile